I have an issue with the Mini, wonder if any else has this problem. I have fired it with some ammo of questionable pedigree, that is to say probably corrosive. On one occasion, I did not clean it for a day or so and the gas port fused itself to the op rod. I had to use a dead blow hammer to free it. It seems that on the blued Minis this part seems very prone to corrosion and that caused these pieces to seize up with one another. This seems to be a bit of a flaw as compared to the chromed gas piston system of the AK

This is an older thread. But I will throw in my $0.02. Just Because...

I have owned both, in large numbers. I like both, and I have no axe to grind.

My thoughts:

Mini-14 or Mini-30:
Bad Magazine design / Execution. I have had mags just fall out. If Mini's were built to the same tolerances as M-14 rifles, this would not exist.
No enough MEAT on the Receiver to Barrel Mate-up. A key to accuracy is to mate up the barrel to the receiver in such a way that there is zero movement. The mini and the AK suffer from this...Lot's of wobble. NOTE: this statement does not refer to Milled AKs. They are the best.
Sights are just awful. Ruger should have made sights that would work out to 300 yards.
Gas system is not all it could be. Clean one once, and you will know what I am talking about. Fail to clean it once and you will really know.

AK - NOT MILLED

Wiggly and wobbly when fired. Yes, every shot goes bang, and every bullet goes downrange. But, hitting an 18" target can get dicey at 300 yards or more. Some AKs are better than others. And, the issues are easily fixed with a thicker, stiffer receiver shell. I had a Hungarian SA-85 that was (literally) hit or miss at 300 yards. I also had an MAK-90 that was just fine and could hold 6" groups at 300 yards. Only real difference was the Hungarian has a 1mm receiver shell, and the MAK-90 has a 1.6mm Receiver shell...

Sights are crap. Just crap. They work, in much the same way an 81mm Mortar sight works.

End result. AK goes BANG. Mini has issues. Mini is more accurate. AK more robust. Mini must be cleaned every 200-300 rounds. AK can go 1000+ rounds before you knot up a boot lace and soak it in dirty motor oil to clean it with.

At the end of the day, both rifles remain very true to their intended purpose.